Pianta



July'4, 1950 u. PlANTA 2,514,350

STRAIGHT-BAR KNITTING MACHINE Filed April 17, 1947 Patented July 4, 1950 UNITE vs esv PATENT o F-Fi "2,514,350 'STRAIGHT BAR KNITTINGTMACHINE 'Ubaldo --Pianta; Milan, Italy, :assignor to Societa Italiana Ernesto; Breda Per Gostruzioni'Meccaniche, Milan, Italy, a firm Application April 17, 1947, Serial No. 742,183 -In Italy February 16, 1946 Sectionl; PublicLaw 690, Aug ust8, 1946 Patent-expires February 16,1966 4 Claims. (CL66- 126) In the straight bar knitting machines known up to'no'w, particularly Cottons machines 'for stockings, the velocity of-the carrier 'rodat the end of each stroke is slowed'by 'm'eans of devic'es comprising an open chain driven at its ends by 'a reciprocating driving bar.

supports are displaceable so as to obtain a variation of the fabric width (or of thestroke of the carrier-rod) that is of the number of meshes; therefore, should the chain be displaced by-displacing one of its sprockets, the carrierrod would be brought out of phasewith" respect to the sinkers.

In order to obviate thisdrawbackfwhichup to now involved the necessity of employing' 'the' reciprocating bar mechanism, the drive *according to the present invention comprises afconnection between the driving member and 'th e driving sprocket mounted on one of the displaceable supports, such that when the support is moved the sprocket is caused to rotate by such an angle as to leave the chain stationarynotwithstanding the displacement of the supportbearing the driving'sprocket. In other words, the connection between the driving member and the driving sprocket isfsuch as to allow the latter to move in a directionfpen pendicular to its axis, causing atthe sametime a rotation of said sprocket equal'toits-"displacement divided by its radius; by this wayth-e displacement of the sprocket involves no displace ment of the chain, as the rotation *(of course in the proper direction) exactly compensates the displacement, that is the sprocket in respect to the chain behaves as rolling on a stationary chain.

Such a connection may be realisedin' different manners; for example the sprocket'might 'be displacing the'movablesupport relativelyto' the driving shaft, the consequent angle of rotation of the driving wheel be exactly as h'ereinbefore specified.

An embodiment of this solution is represented by way of an exam le in the attached drawing, wherein:

iFigfil an elevation ofjthe device;

Fig. 2-is'a plan view o'f'thesame; V Fig. 3 is a cross section of the driving shaft-"on the line A A of Fig. 1.

M "and-the hose -15 drags in turn the carrier or carriers IS.

"The Sprockets 5-*-i '1 -3 9 are loose, that is they rotate free on their journals whereas the "driving sprocket 4 1s fastwith' the pinion'3; The journals of the sprockets 4-4 and 5"-6 are respectively integral with slides II and 18, "which are slidableon the bar 19.

The chain 1| ll driven b ylthesprocket l reciprocates the bar [-3 through the roller I"! and fork The I aim of such known chain devices is to'slow 'theendsof'eachstroke of thecarrier's due tothe chain passing around thejspr ckets' 4+5 indeobtained by increasing or diminishing corre- 'spozidingly the spacing of the slide "l'i with respect to thesli'de l"8,jthe-positions of both slides being controlled by the rods Ila and 1 8a as shown in the drawings.

'It' is established that the displacement of said slides is always symmetric in opposite directions.

It islto be observed *thatthe yoke i2 is open 'atthe bottom and straddles the rotar pin II. Let it be supposed thatthe parts of the device are inthe position shown as Figure l. 'It'isto beun'cl'erstood'that'theshaft l revolves anum ber 'of times in one direction by means of apparatus not here shown and then revolves in the opposite direction for the same number oftimes.

"sprockets 4* and 5 will regulate the -length o'f the bar ceases.

This meansthat through the gear'train 8, 1 and t, the c'hain'iil is 're'ciproca'ted meme direction or the other. Let ussuppose that the "gear chain is movedftoward the left fromthe position in Figure l.' Then, when the yoke l2rides'over the sprocket 4, this yoke-proceeds in a straight line butthe rotary pm i l moves downward frombetween the arms-of the yoke. Thus, at this terminal of the movement the pin 6 l is freed from the yoke and theoperation of the reciprocating Then when the shaft lrotates in the opposite direction the rotary pin i I-icomes up over the sprocket-4- and slips in between thearms of theyoke l2 and consequently causes that yoke andthe chain connected thereto tomove in the opposite direction. Obviously this effect will also 'takeplac'e upon theyoke ofpa'ssing the-sprocket 5. Consequently thespace arranged between the length of the reciprocating stroke of the bar l3 but also of its position.

In conventional devices, the chain (open chain) was dragged at its ends by a supplemental driving bar, as the roller ll must maintain a perfectly symmetric position with respect to the motion, that is the to and fro strokes must be equal.

By the above described device, however, very simple means are employed to obtain the two aims required, that is:

(a) The support I! bearing the driving sprocket 4 is rendered freely displaceable;

(b) The displacement of the slide rotates the pinion 2 and, consequently, pinion 3 and sprocket 4 with the required amplitude and direction.

Two variables can be used at will to attain said correct amplitude of rotation, that is the inclination of the ribs on the shaft l and the transmitting ratio of the gearing 2--3, the only limitation being that the inclination of the spiral ribs must be less than the friction angle between the materials forming the shaft 1 and the pinion 2.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is:

1. In a straight-bar knitting machine, a fixed bar, a pair of slides mounted on said fixed bar for movement along the bar, a pair of freely revoluble sprockets mounted on said bar having fixed axial spacing, a pair of freely revoluble sprockets mounted on said slides, a second pair of sprockets mounted on said slides and having axial relation closer than the first pair of slide supported sprockets the axes of said second pair of sprockets lying in a plane higher than the axes of the first pair of slide mounted sprockets, one of said slides having a shaft journalled therein whereon a sprocket of the second slide supported pair is fixed, a chain extending between and around the first mentioned pair of sprockets to provide runs extending toward each other, said runs extending beneath and up around the first pair of slide supported sprockets and then up to and around the second pair of slide supported sprockets to provide an upper run of said chain extending between said second pair of slide supported sprockets, a reciprocable bar, means releasably connecting said reciprocable bar to fixed part of the I upper run of said chain, and means to effect oscillation of said shaft.

2. In a straight-bar knitting machine, a fixed bar, a pair of slides mounted on said fixed bar for movement along the bar, a pair of freely revoluble sprockets mounted on said bar having fixed axial spacing, a pair of freely revoluble sprockets mounted on said slides, a second pair of sprockets mounted on said slides and having axial relation closer than the first pair of slide supported sprockets the axes of said second pair of sprockets lying in a plane higher than the axes of the first pair of slide mounted sprockets, one of said slides having a shaft journalled therein whereon a sprocket of the second slide supported pair is fixed, a chain extending between and around the first mentioned pair of sprockets to provide runs extending toward each other, said runs extending beneath and up around the first pair of slide supported sprockets and then up to and around the second pair of slide supported sprockets to provide an upper run of said chain extending between said second pair of slide supported sprockets, a reciprocable bar, means releasably connecting said reciprocable bar to a fixed part of the upper run of said chain, a bevel gear fixed on said shaft, a second bevelled gear meshing with the first gear and provided with an axial opening, and an elongated oscillating shaft whereon said second gear is slidably mounted.

3. In a straight-bar knitting machine, a fixed bar, a pair of slides mounted on said fixed bar for movement along the bar, a pair of freely revoluble sprockets mounted on said bar havine fixed axial spacing, a pair of freely revoluble sprockets mounted on said slides, a second pair of sprockets mounted on said slides and having axial relation closer than the first pair of slide supported sprockets the axes of said second pair of sprockets lying in a plane higher than the axes of the first pair of slide mounted sprockets, one of said slides having a shaft journalled therein whereon a sprocket of the second slide supported pair is fixed, a chain extending between and around the first mentioned pair of sprockets to provide runs extending toward each other, said runs extending beneath and up around the first pair of slide supported sprockets and then up to and around the second pair of slide supported sprockets to provide an upper run of said chain extending between said second pair of slide supported sprockets, a reciprocable bar, a downwardly opening yoke fixed to said reciprocable bar, a roller fixed on said chain to engage and disengage from said yoke upon the yoke passing around one of the second pair of slide supported sprockets, and means to effect oscillation of said shaft.

4. In a straight-bar knitting machine, a fixed bar, a pair of slides mounted on said fixed bar for movement along the bar, a pair of freely revoluble sprockets mounted on said bar havin fixed axial spacing, a pair of freely revoluble sprockets mounted on said slides, a, second pair of sprockets mounted on said slides and having axial relation closer than the first pair of slide supported sprockets the axes of said second pair of sprockets lying in a plane higher than the axes of the first pair of slide mounted sprockets, one of said slides having a shaft journalled therein whereon a sprocket of the second slide supported pair is fixed, a, chain extending between and around the first mentioned pair of sprockets to provide runs extending toward each other, said runs extending beneath and up around the first pair of slide supported sprockets and then up to. and around the second pair of slide supported sprockets to provide an upper run of said chain extending between said second pair of slide supported sprockets, a, reciprocable bar, a downwardly opening yoke fixed to said reciprocable bar, a roller fixed on said chain to engage and disengage from said yoke upon the yoke passing around one of the second pair of slide supported sprockets, a bevel gear fixed on said shaft, a second bevelled gear meshing with the first gear and provided with an axial opening, and an elongated oscillating shaft whereon said second gear is slidably mounted.

UBALDO PIANTA.

No references cited. 

